


Too Many Damn Vampires: Vampire Biology in the Barbverse III

by Barb Cummings (Rahirah)



Series: The Barbverse [131]
Category: Angel: the Series, Buffy the Vampire Slayer
Genre: Meta, Vampires, barbverse, vampire biology, vampire population ecology
Language: English
Status: Completed
Published: 2014-07-29
Updated: 2014-07-29
Packaged: 2018-02-10 20:50:31
Rating: General Audiences
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 2,273
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/2039658
Author URL: https://archiveofourown.org/users/Rahirah/pseuds/Barb%20Cummings
Summary: <blockquote class="userstuff">
              <p>So Sunnydale vampires are killing <i>how</i> many people a night again?</p>
            </blockquote>





	Too Many Damn Vampires: Vampire Biology in the Barbverse III

**Author's Note:**

> The statistics presented herein were accurate to the best of my knowledge at the time this essay was written; they may no longer be so. [Vampire Population Ecology](http://spiff.rit.edu/classes/phys317/buffy/vampecology.htm) was an invaluable resource. I also drew on several of the essays which used to be posted on Peasant's Plot; sadly, that site no longer exists.

So how many vampires live in Sunnydale, anyway? The general impression that I get from the show is that there are a minimum of several dozen, and possibly as many as several hundred. But is that a realistic estimate? (Shh. It's only a model.)

Assorted Facts:  
1\. California's death rate in 2000 was 787.2 per 100,000 people. (http://www.statehealthfacts.kff.org)  
Sunnydale's population is approximately 38,500. (Becoming II)  
Sunnydale's death rate per year should therefore be around 300 people, if it were a normal California town. 

2\. California's homicide rate in 2000 was 6 per 100,000 people per year. It has, within the last fifteen years, been as high as 12 per 100,000 people. If Sunnydale has a 12/100,000 homicide rate, then 4.62 of Sunnydale's deaths per year should be due to violent crime (murder, rape, assault, etc.)

3\. Approximately 2% of the population in the U.S. is bitten by dogs per year. (http://www.dogbitelaw.com/PAGES/statistics.html) Sunnydale's emergency rooms ought to see about 770 cases of animal attack per year (possibly a few more thrown in for bear, mountain lion, or other rare-but-possible attacks.) California leads the nation in fatalities from dog bites, but even so, fewer than two people per year die of dog attacks in the entire state. If Sunnydale were a normal town, deaths from animal attack would be extremely rare.

4\. The average human contains 11 pints of blood. 

5\. A human will die of blood loss after losing 4-5 pints of blood, but may die of shock after losing less.

6\. A human takes two months to recover after losing one pint of blood. 

7\. Buffyverse vampires prefer living human blood, but are capable of living on animal blood, or on bagged human blood.

Assumptions:

The average vampire will preferentially consume 2-3 pints of human blood a day. (While I have the greatest respect for peasant_'s calculations, it just seems to me that a big strong vamp like Angelus is going to need more than one pint a day to keep going. YMMV.)

Speculations:

Looking all this over, it seems to me that a town the size of Sunnydale could not possibly support more than a handful of vampires who kill at every (or even most) meals, no matter how stupid the police force or oblivious the population. One human, if captured, could feed five vampires, or one vampire for two or three days (not five, because the human would die of blood loss before all blood was consumed.) If vampires A) hunt in groups, sharing a victim among 2-3 vampires, or B) bring a victim back to the lair to feed on for several days, and assuming that there are only ten vampires in town, 10 vamps at 2 pints a day = 20 pints = two murders per night. There's simply no way that an extra 730 murders/animal fatalities per year can pass unnoticed in a town that size. Even using Peasant's less-hungry vampire model, that's 365 extra deaths per year.

It need not be said that keeping Sunnydale's predator/prey balance to a reasonable, logical, mere handful of very cautious vampires is No Fun At All. So what can we do about this? Well, first of all, how many deaths/attacks can we sneak in before either the vampires eat all the humans or the humans notice something is up and napalm the vampires? Let's say Sunnydale's homicide rate is 18 per 100,000, three times the current average and half again as much as California's highest average in the recent past. That gives us 4.62 deaths per year due to vampires who are smart enough to disguise their kills as 'ordinary' homicides. 

Let us surmise that many vampire kills are not reported, either because the victim is turned, or because (our vampires not being total idiots) the body is hidden or destroyed. Missing persons statistics for Santa Barbara County for 2003 (assuming Sunnydale is in the general vicinity of Santa Barbara) show that of the 426 persons reported missing in 2003, 33 are filed under 'other'--not found, not returned, not discovered dead, etc. (http://caag.state.ca.us/missing/content/03cnty_ad_st.htm) Well, obviously those are vampire victims! 

We now have about thirty-eight deaths/disappearences to play with. That's about 418 pints of blood. Remember that number.

Mgs points out: "Remember Mr Trick says 'Their homicide rate makes DC look like Mayberry, ain't no one saying Boo about it.' (from memory may be slightly wrong) DC homicide rate is currently 46 per 100,000 so I think something around 200 per 100,000 is the Sunnydale rate, not the 18 you use."

That's a good point. Since Mr. Trick didn't give exact numbers, it would be easy enough to fudge here to give us whatever number of dead bodies we need, but one of my basic assumptions is that if the bodies start piling up too high, someone will notice, no matter how hard the Mayor tries to cover it up. And if we're figuring post-S3, then presumably the Sunnydale establishment is a bunch of normal politicians rather than a demonic conspiracy (OK, I realize the line between those two can be pretty thin) and no longer have any ulterior motives to hush up vampire attacks.

There's also the question of which year Trick was referring to--in the mid-90s, DC had a homicide rate of 60 per 100,000. Let's be nice to the vampires and use that figure, since it's likely what Trick was thinking of. However, since that's already a horrendously high number, I'm leery of quadrupling it, due to the people-noticing problem. Let's try just doubling it instead.

That would give us approximately 46 homicide deaths a year. Subtract the approximately five 'normal' homicides one could expect for a SoCal town of that size, add the missing persons, and we've got seventy-four deaths a year to play with. Add in the animal attacks, tote up the pintage, and the increased homicide rate works out to...enough blood to support about one and a half additional vampires for a year.

Basically, killing off humans is a very inefficient way for vampires to feed when they're congregated in large numbers. If all Sunnydale's vampires subsisted solely on human blood from victims who were killed, it would require over 3300 deaths per year--and that's assuming that not a drop of blood was wasted. If the average vampire attack only drained half the victim's blood and the rest was left uneaten when the victim dies, then we're up to well over six thousand deaths a year. In the course of the seven-year run of the show, the vampires would have devoured every human being in Sunnydale. 

So boosting the homicide rate isn't really going to help if we want a sustainable vampire ecology. Are there other sources of death or serious injury that we can exploit? Let's say Sunnydale's animal attack rate is, oh, four times the national average. In addition to those 770 legitimate dog, cat, mountain lion, rabid squirrel and whatever attacks, there are 2310 vampire attacks clogging up the ER every year. Assuming that each attack results in two pints of blood drawn from the victim, that's 4620 pints. If we assume vampires working in pairs, each taking two pints, and leaving the victims on the verge of death but not quite dead yet, we can push that to 9240 pints.

What does that give us? 9658 pints. Divded by 365, that's a bit over 26 pints a day, which works out to thirteen vampires (plus Spike, who's living on pig.) Let's do some more tweaking. It's not very likely that every vampire is successful in every hunt. Lions, for example, succeed in only about one in ten attempts to take down prey. Some of our vampires are going hungry some nights. If one vampire in three fails to catch a human on a given night, I think we can up our vampire population to eighteen. 

This, by the way, is around the number arrived at by the excellent and mostly-incomprehensible-to-me math in the article on Vampire Population Dynamics. And if we're staying at all in the realm of possibility, that's probably where I should stop. But darn it, how can one have intrigue and gang rivalry with a mere eighteen vampires (plus Spike?) Somehow, we need to squeeze a few dozen more in there.

Taking into account human recovery time for blood loss, a vampire could, in theory, feed off two or three people a night, taking a pint from each and leaving them all alive. It would take about a hundred and twenty people to support one vampire and remain in good health themselves (because it takes about two months for a human to recover from donating one pint of whole blood), so if Sunnydale has a population of 38,500, it could support well over three hundred vampires if everyone donated one pint of blood every two months, and no vampire ever killed anyone, and no blood was ever needed for any other medical purposes. Well, that's not a very likely situation, but we know from Into the Woods that there are vampires who choose to survive this way, either by selling their bite to humans, or perhaps just by hit-and-run biting. We could say that there are another dozen 'pacifist' vamps in town who rarely if ever kill humans, and who have a regular 'stable' of humans whom they feed from. Hot damn, thirty vamps plus Spike!

What else? We know that Willy's sells human blood, and that 'everybody' knows about the hospital blood delivery. How much human blood is likely to be available via this route?

San Francisco area blood banks collect about 375 pints per day, from a population of about 750,000, so Sunnydale ought to collect about...twenty pints a day. (And I'm rounding up.) Up to 3% of all whole blood collected is discarded due to exceeding its 42-day shelf life--let's assume that unscrupulous paramedics are selling 10% of the Sunnydale blood bank's take to Willy and/or vampires who buy it direct. That works out to two pints a day--barely enough to support a single vampire. No wonder he charges so much for it. (nb. the high number of exsanguinations will drive up the demand for blood at the hospitals, leading either to increased donations by patriotic Sunnydalians, or shipments from elsewhere. Willy may be able to get as many as four pints a day on the black market.) It doesn't look like this is a viable source of blood for more than one or two vampires. But still, that ups our total to thirty-two.

MustangSally suggests yet another alternate source of blood in funeral homes, which have to exsanguinate bodies before embalming them. The death stats above show that there should be approximately three hundred non-vampire deaths in Sunnydale per year. Not all bodies thus recovered may be fresh enough to be edible, but we may be able to squeeze another two or three vampires in here.

It's also possible that some vampires supplement their diet with rats and stray pets. Such kills would be put down to coyotes. There's also a likelihood that some demons breed small animals for food--kittens, maybe ferrets (the poor vamp's otter?) I have no idea how much blood is in your average cat, but I would guess that one cat or two ferrets or four rats would do for a scant days' feeding. A dog, depending on the size, might feed two vampires for a day, maybe three. 

What about beef or pig's blood? This is actually the most logical way to support a largish vampire population in a small area. Livestock are larger than humans, they're being killed en masse anyway, and both Spike and Angel seemed to have no problem getting a butcher to sell them pig's blood, so we may assume that far more of Sunnydale's vampire population utilizes this resource far more often than they'd like the rest of the world to believe. Bernie and Benny Kohlermann are doing a very thriving business indeed. I'm not going to bother with the math here, because my brain is tired, but I think we could probably fit in another twenty or thirty vampires.

The vampires don't really divide up into neat groups like this, of course--some who always kill humans, some who always feed off willing humans, some who always drink animal blood. The average vampire probably is versatile: usually attacking humans without killing them, occasionally drinking animal blood or going hungry when hunting is poor, and killing a human when an opportunity too good to resist presents itself.

Conclusions:

Sunnydale's vampire population at the time of POM is around 50-60 vampires. This is an extraordinarily high number for a town Sunnydale's size, and the situation only exists due to the Hellmouth. Since Buffy closed it, the vampire population has dropped drastically (there may have been over a hundred vamps in town during its heyday.) Because of the vampire overpopulation problem, hunting in Sunnydale is very poor, and on any given day, half of Sunnydale's vampires are likely to be drinking animal blood, and hating it. Within the next few years it is highly likely that a combination of Slayer activity and emigration will bring the vampire population of Sunnydale down to a dozen or fewer vampires, which is more in line with what a town its size ought to be able to support in comfort and without exciting undue human notice.


End file.
